Modular sleeve for protecting, repairing or renovating a pipe

ABSTRACT

A sleeve (10) for use as a mould for protecting, repairing or renovating a pipe (12) for carrying water, gas or other fluids. A liquid material such as polyurethane or epoxy resin is injected into the sleeve so that, as it polymerizes, it protects or seals the pipe section covered by the sleeve. The sleeve includes a plurality of identical modules (14, 16, 18, 20, 22) assembled to form the mould and each including a male portion and a female portion linked by an intermediate portion. The male portion of one module is designed to fit into the female portion of the adjacent module.

TECHNICAL FIELD

The present invention relates to protection, repair and renovation ofpipes used for carrying water, gas or other fluids, and particularly toa modular sleeve wherein a polymerizable material is injected.

PRIOR ART

Using a sleeve as an injection mould is needed, either to protect thecoupling between two pipes, or to seal off a leak in a pipe. The portionto be protected or repaired is surrounded with the sleeve that forms atight cavity wherein is injected a polymerizable liquid material that,when polymerizing, forms a leak sealing or thermal and chemicalinsulation, anti-shock coating.

Sleeves used in prior art, as set forth for example in patents FR2.158.895, EP 278.050, U.S. Pat. No. 4,610,740 or GB 2.119.884, arecomposed of two cylindrical half-shells linked to form only one shellthat covers the pipe portion to be protected or repaired. Then, thepolymerizable liquid material (generally made up of epoxy orpolyurethane resin components) is poured through an injection holeprovided for in the shell wall into the cavity thus formed.

These sleeves composed of two half-shells are thus suitable for a pipehaving a given diameter. Therefore, it is necessary to have sleeves withvarious diameters capable of fitting the various pipe diameters. Thatway, various moulds are required to manufacture half-shells withdiameters matching all pipe diameters, what leads to a prohibitive cost.

SUMMARY OF THE INVENTION

This is why the object of the invention is to provide a sleeve made upof identical modules requiring only one module manufacturing mould, sucha sleeve being capable of fitting pipes having various diameters throughthe use of the proper number of sleeve modules.

The invention relates therefore to a sleeve meant for protecting,repairing or renovating a pipe carrying water, gas or other fluids,forming an injection mould surrounding the pipe portion to be protectedor repaired, wherein are injected the components of a liquidpolymerizable material that, when polymerizing, provides protection orsealing of the covered pipe portion, said sleeve being made up of aplurality of modules each comprising male, female, and intermediateparts, the male part of a module being designed to fit partially ortotally into the female part of the adjacent module so as to adjust thesleeve to said pipe whose diameter is located within a given range.

BRIEF DESCRIPTION OF THE DRAWINGS

The objects, features and other characteristics of the invention willbecome more apparent from the following detailed description withreference to the accompanying drawings, in which:

FIG. 1 shows in broad outline a modular sleeve covering a pipe portionto be protected or repaired,

FIG. 2 is a top view of a sleeve module according to a preferredembodiment of the invention,

FIG. 3 is a side view, with partial cross-sectional view, of a sleevemodule according to a preferred embodiment of the invention,

FIG. 4 shows in broad outline the cross-sectional view of a fasteningportion located on both sides of the module, and

FIG. 5 shows in broad outline two modules fitted together to make up asleeve according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows in broad outline a sleeve 10 covering a portion of a pipe12 that requires either to be protected (coupling between two pipeends), or to be repaired (leak).

The sleeve 10 shown on FIG. 1 is made of plastic and is composed of aplurality of identical modules such as modules 14, 16, 18, 20, and 22. Apart of each module is fitted into its adjacent module. This way, themodule 18 has a part shown as the dotted line 24 fitted into the module16, the module 20 has a part shown as the dotted line 26 fitted into themodule 18, etc.

The following description relates to the structure of each module shownin top view on FIG. 2 and in side view on FIG. 3.

Each module that makes up the sleeve comprises a central portion 28 thatforms a part of the mould wherein the polymerizable material isinjected, two symmetrical tightening portions 30 and 31 on both sides ofthe central portion, and two symmetrical fastening portions 32 and 33 onboth sides of the tightening portions.

The central portion 28 is composed of three parts, one male part 34, onefemale part 36, and one intermediate part 38. As shown on FIG. 3, theouter surface of the male part 34 has the shape of an arc of a circlehaving a radius R and a centre C1 located lower than the module. Theinner surface of the female part has also the shape of an arc of acircle having a radius R and a centre C2 located lower than the module.Since the outer radius of the male part is equal to the inner radius ofthe female part, the male part of each module can fit easily into thefemale part of the adjacent module.

Each of the tightening portions 30 and 31 located on both sides of thecentral part comprises a tab 40 or 42 having the shape of a right-angledtriangle with a convex hypotenuse (see FIG. 3), located on the same sideas the male part 34 of the module central portion, and an opening 44 or46 whose shape is complementary to the shape of the tabs, located on thesame side as the female part of the central portion. This way, when themale part of a first module is fitted into the female part of a secondadjacent module, the tabs 40 and 42 of the first module are also fittedrespectively into the openings 44 and 46 of the second module.

The two fastening portions 32 and 33 are located on each side of thetightening modules. Each fastening portion comprises a tongue 48 or 50,notched on its upper surface and located on the same side as the malepart of the module central portion, and a tab 52 or 54 having the shapeof a right-angled triangle with a convex hypotenuse.

As it can be seen on FIG. 4 that shows the fastening portion 32 incross-sectional view, the inside of this portion comprises portions 56and 58, notched on their lower surface that is complementary to thenotched upper surface of the tongue 48. That way, when the first moduleis fitted into a second adjacent module, the tongue 48 can be insertedinto the tightening portion 32 of the second module through the openinglocated on the side opposite to the tongue, and passing just above thetab 52. As the first module fits into the second one, the notches oftongue 48 of the first module gear with the notches of the notchedportions 56 and 58, the tongue being held by the non notched portion 57.The notches of the tongue 48 and the complementary notches of portions56 and 58 have a serrated shape so that the tongue cannot move back whenits notches are in gear with those of portions 56 and 58. Therefore, weget a "non-return" effect when fastening modules to each other.

However, the modules may be poorly fitted and may required to bedisassembled to have them properly fitted next. Therefore, it ispreferred to provide for the possibility of disassembling the modules.To this end, the portion 57 (see FIG. 4) located opposite the notchedportions 56 and 58, can be designed to be a movable part so that thenotched tongue can be disengaged from the notched portions 56 and 58,and remove completely said tongue.

The fastening portion also comprises an opening whose shape is similarand complementary to the one of the tab 52 and located under the tongue48 so that, when fitting a first module into a second one, the tab 52 ofthe second module get into the opening 62 of the first module at thesame time as the tongue 48 of the first module gets into the fasteningportion 32 of the second module.

Finally, setting up the modular sleeve is carried out by fitting eachmodule into the module adjacent to it as shown on FIG. 5. The male part34 of a first module is fitted into the female part 36 of a secondadjacent module. At the same time, the notched tongue 48 (or 50) of thefirst module fastening portion is inserted inside the fastening portion321 of the second module. The tabs (40 and 42) of the first moduletightening portions get into the complementary opening (not shown) ofthe second module tightening portions, and the tabs 52' (or 54') of thesecond module get into the openings 44 (or 46) of the first module.

Although it is not shown on the figures, a foam layer is stuck on theinner surface of tightening and/or fastening portions of each module soas to provide a good tightness when the sleeve is in place. But thislayer can also be inserted between the modules and the pipe when thesleeve is being set up.

It must be noted that the tightness of the cavity formed by the centralportion of the sleeve made up by the interlocking of male portions intofemale portions comes normally from the fact that the outer radius R ofeach male part is equal to the inner radius of each female part.However, in order to provide a perfect tightness, it is possible toprovide for a tightness seal on the outer edge of the male part thatgets first into the female part of the adjacent module.

The number of modules used depends on the diameter of the pipe to beprotected or repaired. However, in most cases, the male part 34 does notget fully into the female part 36', as shown on FIG. 5. It is the samefor the notched tongue 48 that gets only partly inside the fasteningportion 32'.

As the modules are fitted into each other, the anti-return or fasteningeffect is reached thanks to the penetration of notched tongues intofastening portions, which prevents the modules from being disconnectedonce fitted. Besides, it is useful to provide for a tool having twobranches meant for grasping the fastening portions and produce atightening force on said portions so as to get a perfect fastening.

When the modules are tightly gripped around the pipe, the sleeve islocked by means of two straps (not shown) arranged around the tighteningportions of the modules. This tightening is required to get a perfecttightness thanks to the foam layer arranged between the pipe and thefastening portions.

It is to be noted that, in order to match a wide range of pipediameters, the shape of the lower profile of each module cannot becircular. As shown on FIG. 3, this profile is made up of two straightparts linked by a part having the shape of an arc of a circle. This way,whatever the number of modules used to make up the sleeve, there is no"break" or knuckle point between the modules. In most cases, the innersurface of each module is practically in line with the inner surface ofthe adjacent module, as shown on FIG. 5. However, it is to be notedthat, since the lower profile of the modules cannot follow closely theouter surface of the pipe, the gap between the two surfaces is balancedby the crushing, more or less intense depending on the location, of thefoam placed between the surfaces and meant for providing a goodtightness.

The modular sleeve set forth above has the advantage of being capable ofmaking up sleeves fitted to various pipe diameters by means of identicalmodules, except one module that comprises a hole to inject thepolymerizable material. Therefore, only one mould is required tomanufacture all the modules. This way, with a module whose centralportion 32 has a base of 80 mm, it is possible to make up sleeves fittedto various pipe diameters by using a number of modules defined asfollow:

    ______________________________________                                        Pipe diameter Number of modules                                               ______________________________________                                        300 MM        12                                                              350 MM                    14                                                  400 MM                    16                                                  450 MM                    18                                                  500 MM                    20                                                  600 MM                    24                                                  ______________________________________                                    

Thus, a given number of modules will match pipe diameters ranging from aminimum value to a maximum value. For example, 16 modules will be usedto fit pipe diameters ranging from 385 MM to 415 MM. This capacity, fora given number of modules, to fit a plurality of pipe diameters isachieved thanks to the interlocking, that can vary within a certainrange, of a plurality of pipe diameters is obtained thanks to theinterlocking, that can vary within a certain range, of the male part ofa module into the female part of the adjacent module, as seen above, andthanks to the compression, that can also vary, of the foam layer locatedunder the tightening portions of the modules.

I claim:
 1. A sleeve for protecting, repairing or renovating a pipecarrying water, gas or other fluids, said sleeve forming a mould forsurrounding the pipe portion to be protected or repaired, wherein isinjected a liquid material such as polyurethane resin that, whenpolymerizing, provides the protection or the sealing of the pipe portioncovered by the sleeve,said sleeve being characterized in that it iscomposed of a plurality of identical modules whose assembling makes upsaid mould, each comprising a male part and a female part linked by anintermediate part, the male part of a module being designed to fitpartially or fully into the female part of the adjacent module so as tofit the sleeve to said pipe whose diameter is located within a givenrange.
 2. The sleeve according to claim 1, wherein said male parts,female parts, and intermediate parts have a cylindrical shape in thelongitudinal direction of the pipe, the cross-section outer profile ofsaid male part having the shape of an arc of a circle with radius R andthe cross-section inner profile of said female part having the shape ofan arc of a circle also with radius R so that the male part of each ofthe modules that make up the sleeve fit perfectly by rotation into thefemale part of the adjacent module.
 3. The sleeve according to claim 1,wherein the inner profiled of each of said modules is made up of twostraight parts linked by an arc of a circle so that the inner surface ofa module be substantially in line with the inner surface of the adjacentmodule when the modules are fitted into each other to make up thesleeve.
 4. The sleeve according to claim 1, wherein each of said modulesmoreover comprises two symmetrical fastening means located on both sidesof the module portion used as a mould, said fastening means being usedas anti-return means for preventing modules from being disassembled assaid male parts are fitted into said female parts.
 5. The sleeveaccording to claim 4, wherein each of said fastening means comprises anotched tongue and at least an inner notched portion designed to gearwith said notched tongue, arranged so that, when fitting the male partof a first module into the female part of a second module, the notchedtongue of the first module get into the fastening means of the secondmodule and gear with the notched portion of the latter so as to providean anti-return effect.
 6. The sleeve according to claim 4, wherein eachof said modules comprises besides two symmetrical fastening means eachlocated between the module portion used as a mould and one of saidfastening means meant for tightening said sleeve around the pipe whensaid modules are assembled.
 7. The sleeve according to claim 6, whereinsaid fastening means of each of said modules comprise a tighteningportion designed to fit into the tightening portion of the adjacentmodule when the modules are being assembled, the tightening beingprovided by means of straps surrounding the tightening portions ofmodules after they are assembled.
 8. The sleeve according to claim 7,wherein a foam layer is arranged between the pipe and said tighteningportions with the aim of providing a good tightness of the sleeve whenthe polymerizable liquid material is injected, said foam beingcompressed when tightening is carried out by means of said straps.